Patents by Inventor Masaki Matsushita

Masaki Matsushita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7176651
    Abstract: An inverter fault detection system of the present invention is provided with: bus voltage monitor means for monitoring the bus voltage of a three-phase inverter; output voltage monitor means for summing the phase output voltages coming from the three-phase PWM inverter, and for outputting the resulting summed output voltage through a filter having a low-pass characteristic of passing through only the cutoff frequency lower than the PWM carrier frequency; and fault determination means for determining that the three-phase PWM inverter is in the faulty state when the output voltage coming from the output voltage monitor means is almost the same as the voltage value corresponding to 3/2 times of the bus voltage monitored by the bus voltage monitor means.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: February 13, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takayuki Kifuku, Masaki Matsushita
  • Patent number: 7161317
    Abstract: An objective is to provide a specific realization means for easily determining malfunction of a system in an electromotive power steering controller. The electromotive power steering controller includes: a voltage controller for controlling voltage applying to a motor based on a d-axis current command value and a q-axis current command value that are set by a d-q-command-value setting unit, and a d-axis current detection value and a q-axis current detection value that are obtained by, using the d-q coordinate system, transforming three-phase ac current that has been actually flowing in the motor and has been detected by a current detector; and a malfunction determining unit for determining that malfunction has occurred in the control system if at least one of the phase-current detection value is out of a first predetermined permissible range.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: January 9, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masaki Matsushita, Takayuki Kifuku, Hiroyuki Kozuki
  • Patent number: 7156509
    Abstract: An image forming apparatus includes an ink tank; and an ink supplying path for supplying the ink from the ink tank to a print head, wherein the ink supplying path therein includes a filter, which generates negative pressure when the ink is supplied, the negative pressure being smaller than ink absorbing pressure of a nozzle of the print head. Further, the ink tank therein includes, for example, a porous ink absorbing body for retaining ink.
    Type: Grant
    Filed: January 28, 2004
    Date of Patent: January 2, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masaki Matsushita, Hirokazu Nakamura, Naozumi Ueno, Hisashi Yoshimura, Takashi Gotoh, Akio Matsumoto, Hiroshi Ishii
  • Patent number: 7141948
    Abstract: An objective is to provide, in a motor controller used for an electromotive power steering system, a concrete realistic method for easily performing abnormality judgments in its control system.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: November 28, 2006
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takayuki Kifuku, Hiroyuki Kozuki, Masaki Matsushita
  • Patent number: 7134748
    Abstract: The present invention can reduce the amount of ink in an outlet-side space which is sucked together with gas, without making the thickness of an isolating member for separating the inside of the sub-tank into an inlet-side space and the outlet-side space in the horizontal direction extremely thin nor making an inflow channel for allowing the ink in the inlet-side space to flow into the outlet-side space extremely small. The present invention has an isolating member in the form of a plate for separating the inside of a sub-tank coupled to a recording head into an inlet-side space connected to a main-tank and an outlet-side space connected to the recording head, and an inflow channel in the form of a slit for increasing the ink level in the inlet-side space while allowing the ink in the inlet-side space to flow into the outlet-side space from the isolating member.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: November 14, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hirokazu Nakamura, Hisashi Yoshimura, Takashi Goto, Naozumi Ueno, Masaki Matsushita, Hiroshi Ishii
  • Patent number: 7106017
    Abstract: A motor control device for a multiple-phase motor includes a drive circuit (PWM inverter) which drives the multiple-phase motor (three-phase DC brushless motor), and a micro-controller that controls the drive circuit, wherein the micro-controller limits a motor current in accordance with an integrated value of a predetermined function of a phase current.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: September 12, 2006
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takayuki Kifuku, Masaki Matsushita
  • Patent number: 7066582
    Abstract: An organic insulating coating formed on a substrate is composed of two layers of a first parylene coating and a second parylene coating. Heat treatment is performed to at least the first parylene coating after being formed, at a temperature below 125° C. for two hours. Then the second parylene coating is formed on the first parylene coating. Occurrence of pinholes is thus prevented at least in one of the two layers of the organic coatings, with the result that insulating properties of the coatings are improved.
    Type: Grant
    Filed: August 8, 2003
    Date of Patent: June 27, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Haruhiko Deguchi, Shigeaki Kakiwaki, Hirotsugu Matoba, Hirokazu Nakamura, Masaki Matsushita, Tomomi Tanaka
  • Publication number: 20060076832
    Abstract: An objective is to provide a specific realization means for easily determining malfunction of a system in an electromotive power steering controller. The electromotive power steering controller includes: a voltage controller for controlling voltage applying to a motor based on a d-axis current command value and a q-axis current command value that are set by a d-q-command-value setting unit, and a d-axis current detection value and a q-axis current detection value that are obtained by, using the d-q coordinate system, transforming three-phase ac current that has been actually flowing in the motor and has been detected by a current detector; and a malfunction determining unit for determining that malfunction has occurred in the control system if at least one of the phase-current detection value is out of a first predetermined permissible range.
    Type: Application
    Filed: August 26, 2005
    Publication date: April 13, 2006
    Inventors: Masaki Matsushita, Takayuki Kifuku, Hiroyuki Kozuki
  • Patent number: 7014303
    Abstract: The invention offers an inkjet printer which does not produce defective prints when bubbles enter ink supply tube. There is provided an air trap in an ink supply tube near an ink delivery port of an ink tank. The air trap is a hollow rectangular parallelepiped with a flow passage length of Lx, a height of Lh as measured from the bottom of an ink flow to a highest part, and a width of W. On its downstream end, the air trap has an outlet having a height of Ly as measured from the bottom of an ink flow. The air trap has a bubble catching space above the outlet. The dimensions are determined so that bubbles float at least up to height Ly while passing through the flow passage of length Lx. When bubbles flow into the air trap, they float and are caught in the space of the air trap before reaching the outlet.
    Type: Grant
    Filed: December 8, 2003
    Date of Patent: March 21, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masaki Matsushita, Hirokazu Nakamura, Naozumi Ueno, Hisashi Yoshimura, Takashi Goto, Hiroshi Ishii
  • Publication number: 20060055243
    Abstract: An objective is to detect a resolver malfunction without fail, using a low-cost resolver having the small number of the poles, and a control-motor system having advantage in small sizing and high-power outputting. In the control-motor system, the system for driving a 2m-pole motor based on a rotor rotation angle ? detected by a 2n-pole resolver, where m and n being counting numbers, is characterized in that: the sum of the square of a signal modulated by sin ? and the square of a signal modulated by cos ? in the resolver in which an excitation signal generated in said system is modulated by sin ? and cos ? in response to the rotor rotation angle ? of the resolver is compared to a predetermined malfunction threshold value, so that malfunction determination related to the resolver is performed, and also, given that the sum is a2 when the resolver is recognized to be in normal operation, the malfunction determination threshold value is made to be not smaller than {a×cos((?/2)/(m/n))}2.
    Type: Application
    Filed: July 11, 2005
    Publication date: March 16, 2006
    Inventors: Masaki Matsushita, Takayuki Kifuku, Hideki Doi, Katsuhiko Ohmae
  • Publication number: 20060056206
    Abstract: An inverter fault detection system of the present invention is provided with: bus voltage monitor means for monitoring the bus voltage of a three-phase inverter; output voltage monitor means for summing the phase output voltages coming from the three-phase PWM inverter, and for outputting the resulting summed output voltage through a filter having a low-pass characteristic of passing through only the cutoff frequency lower than the PWM carrier frequency; and fault determination means for determining that the three-phase PWM inverter is in the faulty state when the output voltage coming from the output voltage monitor means is almost the same as the voltage value corresponding to 3/2 times of the bus voltage monitored by the bus voltage monitor means.
    Type: Application
    Filed: January 28, 2005
    Publication date: March 16, 2006
    Inventors: Takayuki Kifuku, Masaki Matsushita
  • Publication number: 20060043917
    Abstract: An objective is to provide, in a motor controller used for an electromotive power steering system, a concrete realistic method for easily performing abnormality judgments in its control system.
    Type: Application
    Filed: February 28, 2005
    Publication date: March 2, 2006
    Inventors: Takayuki Kifuku, Hiroyuki Kozuki, Masaki Matsushita
  • Publication number: 20060033788
    Abstract: An ink cartridge includes an ink containing section including an ink absorbing body made of a porous material for retaining ink. The ink cartridge satisfies 200?N·R?320, where N is the cell density, expressed in the number of pores per inch, of the ink absorbing body before the ink absorbing body is contained in the ink containing section; and R is a compressibility, which is a volume ratio of the ink absorbing body when the ink absorbing body is contained in a compressed state in the ink containing section to the ink absorbing body before the ink absorbing body is contained in the ink containing section.
    Type: Application
    Filed: September 13, 2005
    Publication date: February 16, 2006
    Inventors: Masaki Matsushita, Hirokazu Nakamura, Naozumi Ueno, Hisashi Yoshimura, Takashi Goto, Hiroshi Ishii
  • Patent number: 6991326
    Abstract: An ink cartridge includes an ink containing section including an ink absorbing body made of a porous material for retaining ink. The ink cartridge satisfies 200?N·R?320, where N is the cell density, expressed in the number of pores per inch, of the ink absorbing body before the ink absorbing body is contained in the ink containing section; and R is a compressibility, which is a volume ratio of the ink absorbing body when the ink absorbing body is contained in a compressed state in the ink containing section to the ink absorbing body before the ink absorbing body is contained in the ink containing section.
    Type: Grant
    Filed: September 16, 2003
    Date of Patent: January 31, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masaki Matsushita, Hirokazu Nakamura, Naozumi Ueno, Hisashi Yoshimura, Takashi Goto, Hiroshi Ishii
  • Patent number: 6906492
    Abstract: A motor abnormality detection apparatus is capable of performing the abnormality detection of a motor (5) without supplying a special electric current thereto for abnormality detection in an ordinary control state. A motor control device (100) controls the motor (5) through vector control which is described by a two-phase rotating magnetic flux coordinate system having the direction of a field current as a d-axis direction and a direction orthogonal to the d-axis direction as a q-axis direction. A motor abnormality detection part (100h) (100h) performs an abnormality determination of the motor based on target impression voltages (Vd*, Vq*) impressed on the motor (5).
    Type: Grant
    Filed: November 20, 2002
    Date of Patent: June 14, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Masaki Matsushita
  • Publication number: 20050123330
    Abstract: A fixing device of the present invention includes a pressure roller and a peeling roller both of which press a heat roller. The pressure roller is disposed upstream to the peeling roller in a transport direction of a recording paper. An outer diameter of the heat roller, an outer diameter of the pressure roller, and an outer diameter of the peeling roller decrease in this order. With this arrangement, it is possible to realize a fixing device which achieves a reduced size and reduced power requirements, while ensuring a fixing property and a peeling property with respect to a recording medium.
    Type: Application
    Filed: December 7, 2004
    Publication date: June 9, 2005
    Inventors: Hisashi Yoshimura, Hirokazu Nakamura, Masaki Matsushita, Hirokazu Fujita, Naozumi Ueno
  • Patent number: 6890057
    Abstract: Ink absorption pads are associated with waste ink storage apparatus in ink jet printers. Waste ink is emitted from the tubes. The waste ink is absorbed by the pads.
    Type: Grant
    Filed: July 1, 2003
    Date of Patent: May 10, 2005
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Gotoh, Hisashi Yoshimura, Naozumi Ueno, Tomomi Tanaka, Masaki Matsushita, Hirokazu Nakamura
  • Publication number: 20050001874
    Abstract: Ink absorption pads are associated with waste ink storage apparatus in ink jet printers. Waste ink is emitted from the tubes. The waste ink is absorbed by the pads.
    Type: Application
    Filed: July 1, 2003
    Publication date: January 6, 2005
    Inventors: Takashi Gotoh, Hisashi Yoshimura, Naozumi Ueno, Tomomi Tanaka, Masaki Matsushita, Hirokazu Nakamura
  • Publication number: 20040217995
    Abstract: An image forming apparatus in which ink depletion detection accuracy will not be deteriorated even if an air bubble is created in an ink supplying path. The mage forming apparatus is provided with (a) an ink storage section for storing ink therein, (b) an ink supplying path for supplying, to a print head, the ink stored in the ink storage section, and (c) an electrode for detecting whether the ink is present or absent in the ink supplying path, an amount of the ink supplied into the ink supplying path being 1.0 cc or less per minute.
    Type: Application
    Filed: January 27, 2004
    Publication date: November 4, 2004
    Inventors: Masaki Matsushita, Hirokazu Nakamura, Naozumi Ueno, Hisashi Yoshimura, Takashi Gotoh, Hiroshi Ishii
  • Publication number: 20040218026
    Abstract: An image forming apparatus includes an ink tank; and an ink supplying path for supplying the ink from the ink tank to a print head, wherein the ink supplying path therein includes a filter, which generates negative pressure when the ink is supplied, the negative pressure being smaller than ink absorbing pressure of a nozzle of the print head. Further, the ink tank therein includes, for example, a porous ink absorbing body for retaining ink.
    Type: Application
    Filed: January 28, 2004
    Publication date: November 4, 2004
    Inventors: Masaki Matsushita, Hirokazu Nakamura, Naozumi Ueno, Hisashi Yoshimura, Takashi Gotoh, Akio Matsumoto, Hiroshi Ishii